Separable fastener biasing system



Aug. 18, 1964 A. G. CARTER ETAL 3,144,696

SEPARABLE FASTENER BIASING SYSTEM Filed May 31, 1962 ANDREW e. CARTER HERMAN e. ALOFS INVENTORS United States Patent 3,144,696 SEPARABLE FASTENER BEASHQG SYSTEM Andrew G. Carter, Grand Rapids, Mich, and Herman G.

Alofs, 1512 Yorkshire SE, Grand Rapids, Mich; said Carter assignor to Andrew G. Carter and Harriett T.

Carter, a partnership doing business as Carter Engineering Company, Grand Rapids, Mich.

Filed May 31, 1962, Ser. No. 198,966 Claims. (Cl. 24-230) This invention has been developed in conjunction with a safety belt buckle mechanism of the type described in the United States patent of Andrew G. Carter, No. 2,965,- 942. The mechanism described in that patent includes separable buckle sections in normally overlapping relationship, with apertures in one section engaging abutments on the other for the transfer of the forces of belt tension. A cam maintains the locking engagement, and a lever pro- Vides for rotating the cam to release position permitting disengagement of the apertures and abutments. The present invention centers in the portions of such a mechanism associated with biasing the cam and lever to the locking position. The prior patent referred to above utilizes separate springs operating on the cam and lever, respectively, so that a light biasing can be applied to the cam and a heavy biasing to the lever (to resist inertia forces without complicating buckle engagement).

The cam and lever are coaxially mounted on the same shaft, and the biasing action is most effectively provided by torsion springs which are mounted on this same shaft. To establish any substantial torque transfer, a portion of the springs must be rotatively fixed with respect to the shaft, with the opposite end bearing on the cam or lever, as the case may be. The present invention provides for the angular fixing of one end of the spring with respect to the shaft in such a manner that facilitates the application of initial biasing on the assembly of the device. The invention is applicable either to the dual-spring arrangement in which separate springs are used on the cam and lever, or on a single spring in which the cam and lever receive their biasing action from the same spring. An example of the latter arrangement is shown in the earlier United States patent of Andrew G. Carter, No. 2,904,866. A single spring may be used to bias the cam and lever into locking position either with the cams formed integrally with the lever, or as a separate member.

In a device embodying this invention, the shaft not only performs the function of rotatively supporting the cam and lever, but also angularly positions a portion of the spring system through the engagement of a noncircular portion of the shaft with a similarly-shaped portion on the spring. This non-circular discontinuity is preferably merely a flattened chordal portion on the shaft, since this is easily provided by conventional rolling procedures utilized in the forming of metal rod stock. A non-circular hole (preferably of a shape to closely receive the cross-section of the shaft) is formed in preferably one side of the frame, the opposite end of the rod being rotatively received within the frame. The preferred form of the invention also utilizes the engagement of the shaft with the non-circular opening of the frame to fix the axial position of the shaft, as well as securing it rotatively. The several features of the invention will be analyzed in further detail through a discussion of the particular embodiment illustrated in the accompanying drawing. In the drawing:

FIGURE 1 is a side elevation, partially in section, showing a complete buckle mechanism in the engaged and locked condition.

FIGURE 2 illustrates the mechanism shown on FIG- release position shown in FIGURE 3.

FIGURE 3 illustrates the mechanism shown in FIG- URE 2, on a reduced scale, in side elevation, and partially in section.

FIGURE 4 illustrates a fragmentary perspective view of the buckle mechanism with the lever in the release position, and with the opposite buckle section not shown.

FIGURE 5 illustrates on an enlarged scale the perspective view of the end of the shaft.

FIGURE 6 is a fragmentary side elevation of the frame of the buckle, illustrating the D-shaped hole for receiving the shaft.

Referring to the drawing, the illustrated mechanism includes the opposite buckle sections generally indicated at 10 and 11, portions of these being in overlapping relationship, and having the abutments 12 on the section 10 interengaged with the apertures 13 on the section 11. A length of belt indicated at 14 is normally secured tothe section 11, and the belt 15 is adjustably received on the section Iii with an arrangement which forms no part of the present invention. The particular adjustable belt connection shown in the drawing is shown, described, and claimed in our copending application Serial No. 198,965, filed on May 31, 1962.

The buckled section 10 includes a frame 16 having spaced parallel sidewalls 17 and 18 provided with aligned holes receiving the shaft 19. A cam member 20 is rotatively mounted on the shaft 19, and has the portions 21 and 22 disposed to bear against the section 11 to main- .tain the interengagement of the abutments 12 and the apertures 13 when the mechanism is in the locking condition shown in FIGURE 1. A lever 23 is also rotatively mounted on the shaft 19, and has a portion 24 disposed to rotatively engage the portions 21 and 22 to rotate the cam member 20 to the release position, as shown in FIG- URE 3'. The lever 23 has spaced sidewalls 25 and 25a receivable between the sidewalls 1'7 and 18 of the frame 16, and also embracing the shaft 19. The lever 23 is preferably provided with a central bearing member 26 also engaging the shaft 19 to stabilize the position of the abutment 27 with respect to the shaft.

A relatively light spring 28 has one end 29 engaging the bar portion 3%) of the cam member 20 to apply a biasing action urging the cam to locking position. The opposite end of the spring 23 has coils of reduced diameter as shown at 31, and these are formed in a D-shaped configuration closely registering with the same general shape of the shaft 19 to effect a lock which prevents angular movement of that end of the spring with respect to the shaft. The constricted portion 31 of the spring will grip the flat 32 of the shaft very effectively, since the resilience of the spring wire can be utilized to remove the need for close tolerances. It should be noted that the remainder of the spring, from the constricted portion 31 to the end '29, is of sufiiciently large diameter to turn freely on the shaft 19.

The spring 33 is also mounted on the shaft 19, with the constricted end 34 engaging the shaft in the same manner as the constricted end 31. The hook-shaped extension 35 at the opposite end of the spring engages the abutment 27 on the cover 23 to apply the biasing action maintaining the lever in the position shown in FIGURE 1. The forces applied by the spring 33 require that the abutment 27 be held firmly with respect to the shaft 19, and this is the prime function of the central bearing portion 26. With this arrangement, the entire lever 23 may be formed of cast plastic material, Without danger that the lever will flex under the forces of the spring 33 enough to release the hook 35 into a space between the abutment 27 and the shaft 19.

The initial assembly of the mechanism shown in the drawing must be accompanied by a sufficient rotation of the shaft 19 to establish the desired biasing action in the springs 28 and 33. Preferably, the hole in the frame wall 17 is circular in shape, permitting full rotation of the shaft 19 until the shaft engages the wall 18 at the opposite side, where the hole 36 receiving the shaft is formed to closely receive the fiat 32 to establish a nonrotative engagement. A transverse notch 37 interrupts the flat 32, and the notch is of sufficient width to receive the thickness of the wall 18. After the shaft 19 has been rotated 21 sufficient amount to develop the necessary torsion in the springs 28 and 33 (with the end of the shaft adjacent, but not entering the hole 36), it is axially pushed into the hole 36 after being placed in proper angular alignment so that the fiat 32 will be properly received. As the axial movement of the shaft continues, a point is reached where the sidewalls of the notch 37 are disposed to receive the wall 18, and the shaft may be torsionally released at this point. The torque of the springs will induce a rotation of the shaft such that the bottom of the notch 37 will then engage the flat side of the hole 36. The engagement of the notch 36 will have the added effect of preventing axial displacement of the shaft 19.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is our intent to claim the entire invention disclosed herein, except as we are limited by the prior art.

We claim:

1. A buckle mechanism comprising:

first and second buckle sections having portions in normally overlapping relationship and having interengaged aperture and abutment means, respectively, on said portions, one of said buckle sections including a frame having opposite side walls provided with aligned holes, one of said holes having a chordal portion, said one buckle section also having:

a shaft normally engaging said holes, said shaft having a chordal portion,

said shaft also having a transverse notch interrupting the chordal portion of said shaft and normally receiving the wall of said frame at said hole to fix the axial and angular position of said shaft with respect to said frame;

cam means rotatably mounted on said shaft and having portions angularly disposed in locking position to bear against the other of said buckle sections to maintain the interengagement of said aperture and abutment means, said cam means being rotatable on said shaft to a release position providing clearance for the disengagement of said aperture and abutment means;

a lever rotatably mounted on said shaft and having abutment means adjacent said shaft and a portion engageable with said cam means to rotate the same to release position,

said lever also having bearing means embracing said shaft adjacent said abutment means;

coil spring means having one end thereof provided with a chordal portion tightly embracing said shaft chordal portion to rotatively fix the said end with respect to said shaft, the opposite end of said spring means biasing said cam means and lever to locking position,

said spring means including separate springs, one of said springs engaging said cam means, and the other engaging said lever abutment means.

2. A buckle mechanism, comprising:

first and second buckle sections having portions in normally overlapping relationship and having interengaged aperture and abutment means, respectively,

on said portions, one of said buckle sections including a frame having opposite side walls provided with aligned holes, one of said holes having a chordal portion, said one buckle section also having:

a shaft normally engaging said holes, said shaft having a chordal portion,

said shaft also having a transverse notch interrupting the chordal portion of said shaft and normally receiving the wall of said frame at said hole to fix the axial and angular position of said shaft with respect to said frame;

cam means rotatably mounted on said shaft and having portions angularly disposed in locking position to bear against the other of said buckle sections to maintain the interengagement of said aperture and abutment means, said cam means being rotatable on said shaft to a release position providing clearance for the disengagement of said aperture and abutment means;

a lever rotatably mounted on said shaft and having a portion engageable with said cam means to rotate the same to release position; and

coil spring means having one end thereof provided with a chordal portion tightly embracing said shaft chordal portion to rotatively fix the said end with respect to said shaft, the opposite end of said spring means biasing said cam means and lever to locking position.

3. A buckle mechanism, comprising: first and second buckle sections having portions in normally overlapping relationship and having interengaged aperture and abutment means, respectively, on said portions, one of said buckle sections including a frame having opposite side walls provided with aligned holes, one of said holes having a discontinuity, said one buckle section also having:

a shaft normally engaging said holes, said shaft having a peripheral axial discontinuity,

said shaft also having a transverse notch forming axially spaced abutments interrupting the discontinuity of said shaft and providing an additional discontinuity thereon, and normally receiving the wall of said frame between axially spaced abutments at said hole to fix the axial and angular position of said shaft with respect to said frame;

cam means rotatably mounted on said shaft and having portions angularly disposed in locking position to bear against the other of said buckle sections to maintain the interengagement of said aperture and abutment means, said cam means being rotatable on said shaft to a release position providing clearance for the disengagement of said aperture and abutment means;

a lever rotatably mounted on said shaft and having a portion engageable with said cam means to rotate the same to release position; and

coil spring means having a plurality of coils at one end thereof provided with a discontinuity tightly embracing said shaft peripheral discontinuity and conforming thereto to rotatively fix the said end with respect to said shaft, the opposite end of said spring means biasing said cam means and lever to locking position.

4. A buckle mechanism, comprising: first and second buckle sections having portions in normally overlapping relationship and having interengaged aperture and abutment means, respectively, on said portions, one of said buckle sections including a frame having opposite side walls provided with aligned holes, at least one of said holes having a discontinuity, said one buckle section also having: a shaft normally engaging said holes, said shaft having a peripheral discontinuity cooperating with the discontinuity of said hole to fix the angular position of said shaft with respect to said frame;

means securing the said shaft axially with respect to said frame;

cam means rotatably mounted on said shaft and having portions angularly disposed in locking position to bear against the other of said buckle sections to maintain the interengagement of said aperture and abutment means, said cam means being rotatable on said shaft to a release position providing clearance for the disengagement of said aperture and abutment means;

a lever rotatably mounted on said shaft and having a portion engageable with said cam means to rotate the same to release position; and

coil spring means having a plurality of coils at one end thereof provided with a discontinuity tightly embracing said peripheral shaft discontinuity and conforming thereto to rotatively fix the said end with respect to said shaft, the

cam means rotatably mounted on said shaft and having portions angularly disposed in locking position to bear against the other of said buckle sections to maintain the interengagement of said aperture and abutment means, said cam means being rotatable on said shaft to a release position providing clearance for the disengagement of said aperture and abutment means;

a lever rotatably mounted on said shaft and having a portion engageable with said cam means to rotate the same to release position; and

coil spring means having a plurality of coils at one end thereof provided with a discontinuity tightly embracing said peripheral shaft discontinuity and conforming thereto to rotatively fix the said end with respect to said shaft, the opposite end of said spring means biasing said cam means and lever to locking position.

References Cited in the file of this patent UNITED STATES PATENTS opposite end of said spring means biasing said cam means and lever to lockin osition 387421 Ken 1888 g P 392,667 Devore Nov. 13, 1888 5. A buckle mechanism, comprising.

1,532,511 Meltz Apr. 7, 1925 first and second buckle sections having portions in cm H W Ila in relationshi nd h Vin t 1,719,422 Breltenbach y 1 n a Y PP g P a a g 9 2,278,650 Drinkwater Apr. 7, 1942 engaged aperture and abutment means, respectively,

2,483,303 Ryslck Sept. 27, 1949 on said portions, one of said buckle sections includ- 2,876,516 Cummings Mar. 10, 1959 mg a frame havlng opposite side Walls provided with 2,904,866 Carter Sept. 22, 1959 allgned holes, at least one of said holes having a 2 965 942 Carter Dec 27 1960 discontinuity, said one buckle section also having:

3,078,538 Brown Feb. 26, 1963 a shaft normally engaglng said holes, said shaft having a peripheral discontinuity; and FOREIGN PATENTS means securing the said shaft axially and angu- 105,689 Great Britain Apr. 26, 1917 larly with respect to said frame; 938,535 Germany Feb. 2, 1956 

1. A BUCKLE MECHANISM COMPRISING: FIRST AND SECOND BUCKLE SECTIONS HAVING PORTIONS IN NORMALLY OVERLAPPING RELATIONSHIP AND HAVING INTERENGAGED APERTURE AND ABUTMENT MEANS, RESPECTIVELY, ON SAID PORTIONS, ONE OF SAID BUCKLE SECTIONS INCLUDING A FRAME HAVING OPPOSITE SIDE WALLS PROVIDED WITH ALIGNED HOLES, ONE OF SAID HOLES HAVING A CHORDAL PORTION, SAID ONE BUCKLE SECTION ALSO HAVING: A SHAFT NORMALLY ENGAGING SAID HOLES, SAID SHAFT HAVING A CHORDAL PORTION, SAID SHAFT ALSO HAVING A TRANSVERSE NOTCH INTERRUPTING THE CHORDAL PORTION OF SAID SHAFT AND NORMALLY RECEIVING THE WALL OF SAID FRAME AT SAID HOLE TO FIX THE AXIAL AND ANGULAR POSITION OF SAID SHAFT WITH RESPECT TO SAID FRAME; CAM MEANS ROTATABLY MOUNTED ON SAID SHAFT AND HAVING PORTIONS ANGULARLY DISPOSED IN LOCKING POSITION TO BEAR AGAINST THE OTHER OF SAID BUCKLE SECTIONS TO MAINTAIN THE INTERENGAGEMENT OF SAID APERTURE AND ABUTMENT MEANS, SAID CAM MEANS BEING ROTATABLE ON SAID SHAFT TO A RELEASE POSITION PROVIDING CLEARANCE FOR THE DISENGAGEMENT OF SAID APERTURE AND ABUTMENT MEANS; A LEVER ROTATABLY MOUNTED ON SAID SHAFT AND HAVING ABUTMENT MEANS ADJACENT SAID SHAFT AND A PORTION ENGAGEABLE WITH SAID CAM MEANS TO ROTATE THE SAME TO RELEASE POSITION, SAID LEVER ALSO HAVING BEARING MEANS EMBRACING SAID SHAFT ADJACENT SAID ABUTMENT MEANS; COIL SPRING MEANS HAVING ONE END THEREOF PROVIDED WITH A CHORDAL PORTION TIGHTLY EMBRACING SAID SHAFT CHORDAL PORTION TO ROTATIVELY FIX THE SAID END WITH RESPECT TO SAID SHAFT, THE OPPOSITE END OF SAID SPRING MEANS BIASING SAID CAM MEANS AND LEVER TO LOCKING POSITION, SAID SPRING MEANS INCLUDING SEPARATE SPRINGS, ONE OF SAID SPRINGS ENGAGING SAID CAM MEANS, AND THE OTHER ENGAGING SAID LEVER ABUTMENT MEANS. 